Mobile communications networks routinely generate and exchange network-specific identifying information between mobile handsets and various network entities. Network specific identifiers (NSIDs) may include information such as a Cell ID identifying the network cell in which the mobile user is currently operating or an MSC address identifying the MSC currently serving the mobile subscriber. NSIDs may not provide a precise location of a particular mobile subscriber because the network specific resource identified by the NSID may be shared by multiple users spread over a given geographical area. For example, the accuracy provided by a Cell ID can be as good as a few hundred meters in urban areas or as poor as 35 km in suburban areas and rural zones, depending on the range of the network base station serving the handset at the time of positioning.
In addition to geographically imprecise information (i.e., NSIDs), mobile communications networks also routinely generate and exchange location information that provides a precise location of mobile users. For example, a mobile handset equipped with a global positioning system (GPS) receiver may determine its geographical position to within an accuracy of +/−5 meters using information provided by multiple orbiting GPS satellites.
In addition to NSIDs and location information, mobile subscribers may generate and exchange presence information with a presence system for indicating the mobile subscriber's status to one or more associated watchers (aka, watching presentities). Typically, presence information is information indicating whether someone's availability to communicate (e.g., via IM). Presence information is also typically expressed in a format that is more easily understood by watchers because watchers are typically other human beings (e.g., friends in an IM list).
One problem associated with using NSID information as input to a presence systems is that NSID information (e.g., MSC identifier, Cell ID, Location Area, etc.) has little or no meaning to a presence system user (e.g., a watcher). Furthermore, indicating to a friend that one is located at 35° 59′N 78° 54′W may be significantly less useful than indicating that one is located “near Southpoint Mall.” Likewise, indicating that one has moved from Cell ID 1214 to Cell ID 1215 is significantly less useful than indicating that one is jogging Downtown.
Another problem associated with presence system geo-location information relates to the distribution of precise geo-location information, such as precise GPS coordinate information once it has been obtained or ascertained. In certain situations, the distribution of precise GPS coordinates (e.g., geo-location coordinates accurate to within a few meters) to watchers may not be desired. For example, a parent may not want for their child to willingly (or unwittingly) allow a watcher to obtain such precise geo-location information associated with their child.
Accordingly, there exists a need for methods, systems, and computer readable media for interworking between NSIDs, location information, and presence systems.